System for fluid transfer

ABSTRACT

A fluid transfer system for use with a valve tree at a well, the valve tree having a wellhead axis, may comprise a header having a header flow axis and a coupler connected to the valve tree and the header and providing fluid communication between the valve tree and the header, the coupler having a coupler flow axis. The sum of the direction changes for a fluid flowing from the header into the valve tree may be less than 225°. The coupler may include a coupler inlet, which may be at substantially the same elevation as the header flow axis. The coupler may be connected to the header such that the coupler flow axis intersects the header flow axis or such that the coupler axis passes between the header axis and the surface of the earth. An angle between the coupler flow axis and the wellhead axis may be acute.

RELATED APPLICATION

This application is a nonprovisional application which claims priorityfrom U.S. provisional application No. 63/301,891, filed Jan. 21, 2022,which is incorporated by reference herein in its entirety.

FIELD OF THE DISCLOSURE

This disclosure relates generally to the field of equipment used infracturing operations.

DESCRIPTION OF THE RELATED ART

In oilfield production operations, some wells may be stimulated toincrease the production of hydrocarbons, such as oil and gas. Suchtechniques may include high-pressure, or hydraulic, fracturing of thewell formation, known to the art as “fracing” a well formation.Generally, in this process a fluid, is pumped into the formationsurrounding the wellbore at high pressure via an assembly of valves,commonly referred to as a frac tree, and related frac fluid pumpingequipment.

BRIEF SUMMARY

The following presents a simplified summary of the disclosed subjectmatter in order to provide a basic understanding of some aspects of thesubject matter disclosed herein.

In an embodiment of the present disclosure, a fluid transfer system foruse with a valve tree at a well, the valve tree having a wellhead axis,comprises a header having a header flow axis and a coupler connected tothe valve tree and the header and providing fluid communication betweenthe valve tree and the header. The coupler may comprise connectors and acoupler conduit that defines a coupler flow axis.

The fluid flow path from the header to the wellhead may include aplurality of direction changes, with none of the direction changes being90°. The coupler may include a coupler inlet and the coupler inlet maybe at substantially the same elevation as the header flow axis or abovethe header flow axis. The coupler may be connected to the header suchthat the coupler flow axis intersects the header flow axis.Alternatively, the coupler may be connected to the header such that thecoupler axis passes between the header axis and the surface of theearth. In some embodiments, the angle between the coupler flow axis andthe wellhead axis may be less than 90°.

The system may include a valve tree multi-path flow connector in fluidcommunication with the valve tree and a flow control valve having a flowaxis. The flow control valve may be directly coupled to the valve treemulti-path flow connector and in fluid communication with the header,and the connection between the coupler and the valve tree may includethe valve tree multi-path flow connector.

The header may include a conduit connected to an inlet through a headermulti-path flow connector and an isolation valve. The valve tree mayinclude a master valve and the valve tree multi-path flow connector maybe disposed vertically above the master valve. The flow axis of the flowcontrol valve may be substantially perpendicular to the flow axis of themaster valve.

The header may further comprise an expansion spool. The system mayfurther comprise an elevating skid positioned beneath the header. Thesystem may further comprise an isolation valve, which may be positionedso as to isolate a section of the header.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is best understood from the following detaileddescription when read with the accompanying figures. It is emphasizedthat, in accordance with the standard practice in the industry, variousfeatures are not drawn to scale. In fact, the dimensions of the variousfeatures may be arbitrarily reduced for clarity of discussion.

FIGS. 1 and 2 are two perspective views from opposite directions of afluid transfer system in accordance with an illustrative embodiment ofthe invention.

FIG. 3 is a side view of some components of the fluid transfer system ofFIG. 1 .

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of various embodiments.Specific examples of components and arrangements are described below tosimplify the present disclosure. These are, of course, merely examplesand are not intended to be limiting. In addition, the present disclosuremay repeat reference numerals and/or letters in the various examples.This repetition is for the purpose of simplicity and clarity and doesnot in itself dictate a relationship between the various embodimentsand/or configurations discussed.

“Master valve”—A master valve is a valve located on a valve tree thatcontrols all flow from a wellbore.

“Directly coupled” means connected without intermediate structure.

This application incorporates by reference the teachings of U.S.Publication Number application Serial No. 2020-0208747 in its entirety.

FIGS. 1-3 depict one embodiment of fluid transfer system 15. Fluidtransfer system 15 includes at least one valve tree 20. While FIGS. 1and 2 depict three valve trees 20, any number of valve trees 20 may beincluded in fluid transfer system 15. Fluid transfer system 15 mayfurther include header 100, such as when fluid transfer system 15includes two or more valve trees 20. In certain embodiments, header 100may supply fluid to valve tree 20, such as, for example and withoutlimitation, pressurized frac fluid. Fluid transfer system 15 alsoincludes coupler 207 fluidly coupling header 100 to valve tree 20.Although in the embodiment shown in FIGS. 1 and 2 , each valve tree 20includes only one coupler 207 fluidly communicating with header 100,multiple couplers 207 may be used to fluidly communicate between asingle valve tree 20 and header 100. Each coupler 207 preferablyincludes a coupler flow path that is inclined from the horizontal, asdiscussed in more detail below.

As further depicted in FIGS. 1 and 2 , each valve tree 20 is associatedwith a wellhead 16, wherein each wellhead 16 is connected to ahydrocarbon well. Pads 17 adjacent each wellhead 16 may be well cellaropenings surrounding each wellhead 16 that provide access to the welland the portion of the wellhead 16 disposed below the earth's surface.Each valve tree 20 has a substantially vertical wellhead axis 217 andincludes master valve 25. Valve tree 20 may optionally include a secondmaster valve 26. Opening master valve 25 and/or second master valve 26allows fluid flow into or out of the well through valve tree 20 andwellhead 16.

Header 100 may be connected to a fluid source for the provision of fluidsuch as a pressurized frac fluid to header 100. Inlet 101 may includeone or more fittings 102, to which hoses or piping may be connected.Header 100 may also include at least one header multi-path flowconnector 103 to which inlet 101 connects.

Header 100 may further include conduit 104 for connecting multi-pathflow connector 103 to a second multi-path flow connector 103. In thepresent illustrative embodiment of fluid transfer system 15, threemulti-path flow connectors 103 and two lengths of conduit 104 are shown.As is appreciated by those of ordinary skill in the art, any number ofconduits 104 and header multi-path flow connectors 103 may be similarlyconnected. Although inlet 101 is shown at an end of header 100, ifdesired inlet 101 may be disposed at a location intermediate, orbetween, the ends of header 100. Header 100 may include optionalisolation valve 109 positioned between header multi-path flow connector103 and conduit 104 or between sections of conduit 104 so as to isolateflow from adjacent header multi-path flow connectors 103.

Conduit 104 may be formed of one or multiple spools 120. Spools 120 maybe connected to isolation valves 109 and to header multi-path flowconnector 103 by spool connections, which may be flanged connections,studded connections, threaded connections or quick connect connectors.If desired, one or more expansion spools 122, may form part of conduit104. Each expansion spool 122 can be adjustably extended in alongitudinal direction. By adjusting the length of expansion spool 122,coupler 207 may be aligned with a respective valve tree 20.

Header multi-path flow connectors 103 may, in certain non-limitingexamples, comprise studded or flanged flow tees. For example, a headermulti-path flow connector 103 may comprise a studded three-way orfour-way flow tee that permits flow through header multi-path flowconnectors 103 both along the longitudinal axis 136 of header 100 andalso out of conduit 104 into coupler 207. If a four-way flow tee isused, flow may pass into a studded flow tee, or three-way block, whichmay in turn be used as auxiliary, or supplemental, inlets to, or outletsfrom, header 100.

In circumstances where only one valve tree 20 is present, header 100 maybe omitted. As with embodiments where a plurality of valve trees 20 arepresent, the one valve tree embodiment includes multi-path flowconnector 103 that provides a flow path from inlet 101 to coupler 207.

Header 100 may be supported by at least one elevating skid 115.Elevating skid 115 may allow vertical adjustment of header 100, therebyadjusting the vertical elevation of one end of coupler 207. In certainnon-limiting embodiments, each elevating skid 115 may rest on theearth's surface, on a pad, or on metal skids. The support for eachelevating skid 115 may include height adjusting leveling supports. Whileshown in FIGS. 1 and 2 as positioned beneath header multi-path flowconnectors 103 elevating skids 115 may be positioned as desired alongheader 100.

As described above, each valve tree 20 may be connected to a respectivecoupler 207 for fluid communication with header 100 and inlet 101. Incertain embodiments, coupler 207 has a fixed length, meaning that thereare no expansion joints or other mechanisms designed to adjust thelength or height of coupler 207. In other embodiments, coupler 207 mayinclude an expansion joint or other mechanism configured to adjust thelength of coupler 207. Each coupler 207 has a longitudinal coupler axis224.

Coupler 207 may include a header coupler connector 205, a couplerconduit 200, and a valve tree coupler connector 210. Coupler 207 may befluidly coupled to header 100 by header coupler connector 205 and joinedto valve tree 20 by valve tree coupler connector 210. Coupler conduit200 defines longitudinal coupler axis 224. Coupler 207 may be configuredsuch that no two consecutive flow directions within coupler 207 areperpendicular to one another. In some embodiments, header couplerconnector 205 valve tree coupler connector 210 each cause a change of45° in the direction of fluid flow.

Coupler 207 may be connected to header 100 such that coupler axis 224intersects header axis 136 or passes above header axis 136. In otherembodiments, coupler conduit 200 may be connected to header 100 suchthat coupler axis 224 passes between header axis 136 and the surface ofthe earth. Header coupler connector 205 and valve tree coupler connector210 may each be an angled coupler that provides a change in thedirection of fluid flow.

In certain embodiments, coupler 207 may be joined directly to header100. In embodiments in which header coupler connector 205, a couplerconduit 200, and a valve tree coupler connector 210 connects to valvetree 20 at a higher elevation, coupler conduit 200 may be inclined suchthat coupler axis 224 defines an angle α with respect to horizontal(FIG. 3 ). In some embodiments, α may be between 0° and 90°, or between10° and 80°. In some embodiments, α may be 45°. While header couplerconnector 205 and valve tree coupler connector 210 are illustrated aseach producing a direction change of about 45°, alternative angles arepossible.

In some embodiments, coupler axis 224 may not be perpendicular to headeraxis 136. By way of example, space constraints may make it advantageousto fit the various components of fluid transfer system 15 closelytogether, thereby constraining the positioning of the various componentsof system 15.

Header coupler connector 205 and valve tree coupler connector 210 mayeach be connected to the adjacent equipment by means of bolted flangesor the like. In some embodiments, at least one of header couplerconnector 205 and valve tree coupler connector 210 may be configured toallow at least some relative rotation. By way of example, header couplerconnector 205 may be configured to allow rotation of coupler conduit 200relative to header 100.

In addition to providing a quick and efficient connecting of eachcoupler to its respective frac tree, coupler connectors 205, 210 mayfacilitate the efficient and safe installation and removal of coupler207. Additionally, use of coupler 207 permits a user of fluid transfersystem 15 to quickly disassemble, or “rig down”, the fluid transfersystem 15 to access master valves 25, 26 for replacement of one or moremaster valves 25, 26.

In certain embodiments, coupler conduit 200 may include at least twowing valves 215. In some embodiments, four wing valves 215 may be used,for instance, where two of wing valves 215 are disposed approximately180 degrees apart from the other two wing valves 215 and may form a row,the row having a wing valve axis 216.

Referring particularly to FIG. 1 , coupler 207 may include at least oneflow control valve 220. Flow control valve 220 may have a flow axis 223that is perpendicular to axis 216 defined by wing valves 215 and issubstantially parallel to the surface of the earth. Flow axis 223 mayalso be perpendicular to the vertical axis of valve tree 20. Flowcontrol valve 220 may be used to control the flow of fluid from header100 to each valve tree 20. Flow control valve 220 may have internal boredimensions that are greater than or equal to the internal bore dimensionof, master valves 25, 26. In some embodiments, flow control valve 220may be directly coupled to a valve tree multi-path flow connector 260.In certain embodiments, for example if fluid transfer system 15 is usedwith a single frac tree, coupler 207 may not include flow control valve220.

Each coupler 207 may include or be in fluid communication with a swabvalve 230 on its respective valve tree 20. In other embodiments, swabvalve 230 is connected to coupler 207 by a flanged connection, studdedconnection, threaded connection, clamp, or quick connect connector.

Valve tree multi-path flow connector 260 may be any suitable device,including but not limited to: a multi-path flow connector with threefluid connection ports, a studded 5-way flow cross or a 6-way flow crosswith a blind flange may be positioned below swab valve 230. Valve treemulti-path flow connector 260 may be in fluid communication with: swabvalve 230; wing valves 215; flow control valve 220; and valve tree 20.In certain embodiments, flow control valve 220 is directly connected tovalve tree multi-path flow connector 260 without any intervening pipingor components.

During the drilling of a well, wellhead 16 may be installed on eachwell. Valve tree 20 may be connected to wellhead 16. Master valves 25,26 are installed, or attached, to wellhead 16. When it is desired toprovide fracing fluid to two or more wells, header 100 may be positionedin a spaced relationship from the wellheads 16 and couplers 207 may beused to provide fluid communication between the header and each fractree.

As indicated above, coupler 207 may be configured such that no twoconsecutive flow directions within coupler 207 are perpendicular to oneanother. Each change of direction reduces the fluid pressure andincreases wear on equipment. By reducing the number of 90° changes influid flow direction, the present system reduces the amount by which thefluid must change direction as it passes from header 100 to wellhead 16,thereby also reducing the fluid pressure loss and wear on equipment.

Coupler 207 may be assembled at the well site; in other embodiments, thecomponents of the coupler 207 are preassembled at another location.Coupler 207 may be transported to the well site and be lifted, such asby a crane or other suitable lifting device and positioned above header100 and valve tree 20. Coupler 207 may be lowered and connected toheader 100 and valve tree 20, using header coupler connector 205 andvalve tree coupler connector 210. When header coupler connector 205 andvalve tree coupler connector 210 are flanged or studded connectors,header coupler connector 205 and valve tree coupler connector 210 may beaffixed with bolts. Alternatively, quick connect connectors may be usedfor header coupler connector 205 and valve tree coupler connector 210.

If fluid transfer system 15 includes a plurality of valve trees 20,additional portions of header 100 may be assembled, as shown in FIGS. 1and 2 . These additional portions of header 100 are assembled in themanner previously described and are mounted on elevating skids 115 andare each disposed in a spaced relationship from wellheads of eachadditional valve tree 20. As previously described, these additionalsections are fluidly connected, so that header 100 appears as shown inFIGS. 1 and 2 . Each additional coupler 207 may be connected betweenheader 100 and a valve trees 20 as shown in FIGS. 1 and 2 . Fluidtransfer system 15 may be enlarged for use with additional valve trees,as by attaching additional portions of the header 100 and couplers.

While several exemplary embodiments have been provided in the presentdisclosure, it may be understood that the disclosed embodiments might beembodied in many other specific forms without departing from the spiritor scope of the present disclosure and the appended claims. The presentexamples are to be considered as illustrative and not restrictive, andthe intention is not to be limited to the details given herein. Forexample, the various elements or components may be combined orintegrated in another system or certain features may be omitted, or notimplemented.

In addition, the various exemplary embodiments described and illustratedin the various embodiments as discrete or separate may be combined orintegrated with other systems, modules, techniques, or methods withoutdeparting from the scope of the present disclosure. Other examples ofchanges, substitutions, and alterations are ascertainable by one skilledin the art and may be made without departing from the spirit and scopedisclosed herein.

We claim:
 1. A fluid transfer system for use with a valve tree at awell, the valve tree having a wellhead axis, the system comprising: aheader having a header flow axis; and a coupler connected to the valvetree and the header and providing fluid communication between the valvetree and the header, the coupler having a coupler flow axis; wherein thecoupler is configured such that no two consecutive flow directionswithin the coupler are perpendicular to one another.
 2. The system ofclaim 1 wherein the coupler includes a coupler inlet and wherein thecoupler inlet is at substantially the same elevation as the header flowaxis
 3. The system of claim 1 wherein the coupler includes a couplerinlet and wherein the coupler flow axis passes above the header flowaxis.
 4. The system of claim 1 wherein the coupler is connected to theheader such that the coupler flow axis passes between the header axisand the surface of the earth.
 5. The system of claim 1 wherein thecoupler includes a coupler conduit defining the coupler flow axis andwherein the coupler flow axis intersects the header flow axis.
 6. Thesystem of claim 1 wherein the system includes a multi-path flowconnector in fluid communication with the valve tree and a flow controlvalve having a flow axis, the flow control valve directly coupled to themulti-path flow connector and in fluid communication with the header,and wherein the connection between the coupler and the valve treeincludes the multi-path flow connector.
 7. The system of claim 6 whereinthe header includes a conduit connected to an inlet through a headermulti-path flow connector and an isolation valve.
 8. The system of claim7, wherein the conduit includes an expansion spool.
 9. The system ofclaim 6 wherein the valve tree includes a master valve, wherein thevalve tree multi-path flow connector is disposed vertically above themaster valve, and wherein the flow axis of the flow control valve issubstantially perpendicular to the flow axis of the master valve. 10.The system of claim 6, wherein the multi-path flow connector comprises astudded or flanged flow tee.
 11. The system of claim 1, wherein thecoupler has a fixed length.
 12. The system of claim 1, wherein thecoupler includes an expansion joint.
 13. The system of claim 1, whereinthe coupler is connected to the header by a header coupler connectionand to the valve tree by a valve tree coupler connector.
 14. The systemof claim 13, wherein the header coupler connector and the valve treecoupler connector are each adapted to cause a change of 45° in thedirection of fluid flow.
 15. The system of claim 1 wherein the headerfurther comprises an expansion spool.
 16. The system of claim 1, furthercomprising an elevating skid, the elevating skid positioned beneath theheader.
 17. The system of claim 1, further comprising an isolationvalve, wherein the isolation valve is positioned so as to isolate asection of the header.